{
  lib,
  pkgs,
  config,
  ...
}:
let
  self = config.flakeDeclared.lingual.ja_JP;
in
{
  options.flakeDeclared.lingual.ja_JP = {
    enable = lib.mkEnableOption "Japanese (Japan) locale";
  };
  config = lib.mkIf self.enable {
    i18n.supportedLocales = [
      "ja_JP.UTF-8/UTF-8"
      "ja_JP.EUC-JP/EUC-JP"
    ];
    fonts.packages = with pkgs; [
      source-han-serif
      source-han-sans
      source-han-mono
      noto-fonts-cjk-serif
      noto-fonts-cjk-sans
    ];
  };
}
